A baby who never uttered a word touched the hearts of nearly a million people. A second-grader with so much courage, people around the world called him a hero. A 6-year-old boy who was never supposed to walk—and now won't stop running. The stories of these miracle children can make you believe that anything is possible.

Oprah met her first two little miracle guests when they were just 4 years old. Conjoined twins Kendra and Maliyah Herrin were born sharing a large intestine, bladder, liver and single kidney. Each sister had two arms, but just one leg. The survival rate for conjoined twins is extremely low, but the girls exceeded all expectations and even learned to crawl—something doctors said might never happen.